Zinc and Men's Health: Does It Really Help Testosterone and Sperm?

Zinc is one of the supplements men ask me about most, because ads often say it will "boost testosterone, boost sperm and cure premature ejaculation". I used to write about zinc very positively myself, but after reviewing newer research, let me tell you straight: zinc really is important, but it doesn't do everything the ads claim.

What zinc does in a man's body

Zinc is a mineral the body uses in hundreds of enzymes. Its roles related to men's health include:

• Being part of the process of making testosterone in the testes
• Being highly concentrated in the prostate and semen, where it is used to make sperm and help them move
• Supporting the immune system, wound healing and the senses of taste and smell

The real evidence: what it can and can't do

In short, if your problem is erections, premature ejaculation or wanting a baby, zinc is not the main answer. Reading Erectile dysfunction (ED), Premature ejaculation (PE) and Semen analysis will get you closer to the point.

Genuinely helps

• If you are deficient, supplements can restore normal hormones
• Inflammatory acne: a small benefit
• Immunity and wound healing

Not enough evidence

• Raising testosterone when levels are normal
• Improving sperm quality (FAZST, JAMA 2020)
• Fixing premature ejaculation or ED
• Preventing prostate enlargement or DHT hair loss

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Who is at risk of zinc deficiency

• Strict vegetarians or vegans (phytates in grains and beans reduce absorption)
• Heavy drinkers
• People with chronic bowel disease, chronic diarrhea or previous weight-loss stomach surgery
• Poorly controlled diabetes, chronic kidney disease or liver disease
• Older people who eat very little

Possible signs of deficiency include poor appetite, a change in taste, slow wound healing, hair loss, skin rashes and frequent infections, none of which are specific. Blood zinc levels are also hard to interpret, because they change with inflammation and the time of day the blood is taken. So I always look at the history and the whole picture as well.

How much the body needs, and the safe upper limit

• Adult men need about 11 mg a day
• The upper limit not to exceed long term is 40 mg a day (from food and supplements combined)
• Six oysters contain more zinc than a whole day's requirement; 90 g of beef has about 4–7 mg; 30 g of pumpkin seeds has about 2 mg

Taking too much causes nausea, vomiting and stomach pain, and high doses for several months compete with copper absorption, leading to anemia, low white blood cells and possible nerve problems. Zinc also reduces the absorption of some antibiotics, so take them at least 2 hours apart.

< 11 mgMay be too littleAt-risk: vegans, heavy drinkers, bowel disease

≈ 11 mgA man's requirementFrom food: oysters, red meat, beans

≤ 40 mgLong-term upper limitTotal of food, supplements and cold lozenges

> 40 mgToo much: side-effect riskNausea, copper deficiency, anemia, low white cells

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If you want to look after your testosterone, where to start instead

Factors that affect hormones more than supplements are body weight, waist size, sleep, exercise, stress and chronic illness. See the evidence-based approaches in Optimising testosterone with sleep, food and exercise. If you suspect low testosterone, have a morning blood test done properly; see Testosterone basics every man should know.

For other herbs and supplements marketed for sex, read on in Do herbs really help sexual health?

When to see a doctor

See a doctor if you have symptoms of low testosterone, such as a clear drop in sex drive, fatigue, low mood or loss of muscle, if you have had erection problems for more than 3 months, or if you have been trying for a baby for more than a year without success.

At Dr. Kris Clinic I assess your symptoms, chronic conditions, medicines and the supplements you already take, test hormones or semen when there is a reason, and advise you on what to keep taking and what to stop, so you don't spend money on supplements you don't need.